A downhole tool such as a packer is used as an isolation device to seal a region in a borehole. Additionally, packers are often used to isolate sections of the borehole from one another. For example, a toroid-shaped packer can be used to fill the annular space between a production tube and the casing or wall of a borehole. In some circumstances, a disc- or column-shaped packer is used to isolate a borehole that is free of production tubing. With either application, the packer must tightly seat against the wall, casing, and production tubing (if present) to form an effective seal. Packers can form these seals by expanding to fill the void volume in the borehole. Expansion can occur by increasing the packer's volume via absorbing a fluid. The spotting position of the packer can occur at several thousand feet downhole. While traversing the borehole en route to this destination, the packer is typically in contact with the fluid in the borehole. Problems can occur when the packer absorbs this fluid and expands before reaching the target depth. When the packer expands, it may become stuck in an undesired position within the borehole. In this event, extraction of the packer may be required. This can be a costly and time-consuming process.
Devices, methods, and materials that overcome the above problems would be well-received by those skilled in the art.